From 8d10f1dc6daaa2ac5050b79942c7d35949889a14 Mon Sep 17 00:00:00 2001
From: Brendan Zabarauskas <bjzaba@yahoo.com.au>
Date: Sat, 26 Mar 2016 13:19:06 +1100
Subject: [PATCH] Remove extraneous operator overloads on vectors, and add
 Elementwise trait

---
 src/array.rs    | 16 ++++++++++
 src/lib.rs      |  2 --
 src/num.rs      | 21 +++++++++++--
 src/prelude.rs  |  1 +
 src/vector.rs   | 80 ++++++++++++++++++++-----------------------------
 tests/vector.rs | 29 ------------------
 6 files changed, 67 insertions(+), 82 deletions(-)

diff --git a/src/array.rs b/src/array.rs
index 3536371..f71c37f 100644
--- a/src/array.rs
+++ b/src/array.rs
@@ -57,3 +57,19 @@ pub trait Array where
     /// The maximum element of the array.
     fn max(self) -> Self::Element where Self::Element: PartialOrd;
 }
+
+/// Element-wise arithmetic operations. These are supplied for pragmatic
+/// reasons, but will usually fall outside of traditional algebraic properties.
+pub trait ElementWise<Rhs = Self> {
+    fn add_element_wise(self, rhs: Rhs) -> Self;
+    fn sub_element_wise(self, rhs: Rhs) -> Self;
+    fn mul_element_wise(self, rhs: Rhs) -> Self;
+    fn div_element_wise(self, rhs: Rhs) -> Self;
+    fn rem_element_wise(self, rhs: Rhs) -> Self;
+
+    #[cfg(feature = "unstable")] fn add_assign_element_wise(&mut self, rhs: Rhs);
+    #[cfg(feature = "unstable")] fn sub_assign_element_wise(&mut self, rhs: Rhs);
+    #[cfg(feature = "unstable")] fn mul_assign_element_wise(&mut self, rhs: Rhs);
+    #[cfg(feature = "unstable")] fn div_assign_element_wise(&mut self, rhs: Rhs);
+    #[cfg(feature = "unstable")] fn rem_assign_element_wise(&mut self, rhs: Rhs);
+}
diff --git a/src/lib.rs b/src/lib.rs
index de3cb52..cedfe42 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -27,8 +27,6 @@
 //! `look_at`, `from_angle`, `from_euler`, and `from_axis_angle` methods.
 //! These are provided for convenience.
 
-#![cfg_attr(feature = "unstable", feature(augmented_assignments, op_assign_traits))]
-
 extern crate num as rust_num;
 extern crate rustc_serialize;
 extern crate rand;
diff --git a/src/num.rs b/src/num.rs
index f6e74d0..c29a07e 100644
--- a/src/num.rs
+++ b/src/num.rs
@@ -17,6 +17,8 @@ use approx::ApproxEq;
 
 use std::cmp;
 use std::fmt;
+#[cfg(feature = "unstable")]
+use std::ops::*;
 
 use rust_num::{Float, Num, NumCast};
 
@@ -60,9 +62,22 @@ partial_ord_float!(f64);
 
 
 /// Base numeric types with partial ordering
-pub trait BaseNum:
-    Copy + NumCast + Clone + Num
-    + PartialOrd + cmp::PartialOrd + fmt::Debug
+#[cfg(not(feature = "unstable"))]
+pub trait BaseNum where
+    Self: Copy + Clone + fmt::Debug,
+    Self: Num + NumCast,
+    Self: PartialOrd + cmp::PartialOrd,
+{}
+
+
+/// Base numeric types with partial ordering
+#[cfg(feature = "unstable")]
+pub trait BaseNum where
+    Self: Copy + Clone + fmt::Debug,
+    Self: Num + NumCast,
+    Self: PartialOrd + cmp::PartialOrd,
+    Self: AddAssign + SubAssign,
+    Self: MulAssign + DivAssign + RemAssign,
 {}
 
 
diff --git a/src/prelude.rs b/src/prelude.rs
index a7ad11c..edbfc0f 100644
--- a/src/prelude.rs
+++ b/src/prelude.rs
@@ -5,6 +5,7 @@
 pub use angle::Angle;
 
 pub use array::Array;
+pub use array::ElementWise;
 
 pub use matrix::Matrix;
 pub use matrix::SquareMatrix;
diff --git a/src/vector.rs b/src/vector.rs
index b7b9ed8..956c185 100644
--- a/src/vector.rs
+++ b/src/vector.rs
@@ -40,7 +40,7 @@
 //! let b: Vector2<f64> = Vector2::new(-3.0, -4.0);
 //!
 //! assert_eq!(a + b, Vector2::zero());
-//! assert_eq!(-(a * b), Vector2::new(9.0f64, 16.0f64));
+//! assert_eq!(-(a * 2.0), Vector2::new(-6.0, -8.0));
 //!
 //! // As with Rust's `int` and `f32` types, Vectors of different types cannot
 //! // be added and so on with impunity. The following will fail to compile:
@@ -97,24 +97,17 @@ use rust_num::{NumCast, Zero, One};
 
 use angle::{Angle, Rad};
 use approx::ApproxEq;
-use array::Array;
+use array::{Array, ElementWise};
 use num::{BaseNum, BaseFloat, PartialOrd};
 
-/// A trait that specifies a range of numeric operations for vectors. Not all
-/// of these make sense from a linear algebra point of view, but are included
-/// for pragmatic reasons.
+/// A trait that specifies a range of numeric operations for vectors.
 pub trait Vector: Copy + Clone where
     // FIXME: Ugly type signatures - blocked by rust-lang/rust#24092
     Self: Array<Element = <Self as Vector>::Scalar>,
 
     Self: Add<Self, Output = Self>,
     Self: Sub<Self, Output = Self>,
-    Self: Mul<Self, Output = Self>,
-    Self: Div<Self, Output = Self>,
-    Self: Rem<Self, Output = Self>,
 
-    Self: Add<<Self as Vector>::Scalar, Output = Self>,
-    Self: Sub<<Self as Vector>::Scalar, Output = Self>,
     Self: Mul<<Self as Vector>::Scalar, Output = Self>,
     Self: Div<<Self as Vector>::Scalar, Output = Self>,
     Self: Rem<<Self as Vector>::Scalar, Output = Self>,
@@ -216,7 +209,7 @@ macro_rules! impl_vector {
 
             #[inline] fn from_value(scalar: S) -> $VectorN<S> { $VectorN { $($field: scalar),+ } }
 
-            #[inline] fn dot(self, other: $VectorN<S>) -> S { (self * other).sum() }
+            #[inline] fn dot(self, other: $VectorN<S>) -> S { $VectorN::mul_element_wise(self, other).sum() }
         }
 
         impl<S: Neg<Output = S>> Neg for $VectorN<S> {
@@ -242,28 +235,16 @@ macro_rules! impl_vector {
             }
         }
 
-        impl_operator!(<S: BaseNum> Add<S> for $VectorN<S> {
-            fn add(vector, scalar) -> $VectorN<S> { $VectorN::new($(vector.$field + scalar),+) }
-        });
         impl_operator!(<S: BaseNum> Add<$VectorN<S> > for $VectorN<S> {
             fn add(lhs, rhs) -> $VectorN<S> { $VectorN::new($(lhs.$field + rhs.$field),+) }
         });
-        impl_assignment_operator!(<S: BaseNum> AddAssign<S> for $VectorN<S> {
-            fn add_assign(&mut self, scalar) { $(self.$field += scalar);+ }
-        });
         impl_assignment_operator!(<S: BaseNum> AddAssign<$VectorN<S> > for $VectorN<S> {
             fn add_assign(&mut self, other) { $(self.$field += other.$field);+ }
         });
 
-        impl_operator!(<S: BaseNum> Sub<S> for $VectorN<S> {
-            fn sub(vector, scalar) -> $VectorN<S> { $VectorN::new($(vector.$field - scalar),+) }
-        });
         impl_operator!(<S: BaseNum> Sub<$VectorN<S> > for $VectorN<S> {
             fn sub(lhs, rhs) -> $VectorN<S> { $VectorN::new($(lhs.$field - rhs.$field),+) }
         });
-        impl_assignment_operator!(<S: BaseNum> SubAssign<S> for $VectorN<S> {
-            fn sub_assign(&mut self, scalar) { $(self.$field -= scalar);+ }
-        });
         impl_assignment_operator!(<S: BaseNum> SubAssign<$VectorN<S> > for $VectorN<S> {
             fn sub_assign(&mut self, other) { $(self.$field -= other.$field);+ }
         });
@@ -271,42 +252,51 @@ macro_rules! impl_vector {
         impl_operator!(<S: BaseNum> Mul<S> for $VectorN<S> {
             fn mul(vector, scalar) -> $VectorN<S> { $VectorN::new($(vector.$field * scalar),+) }
         });
-        impl_operator!(<S: BaseNum> Mul<$VectorN<S> > for $VectorN<S> {
-            fn mul(lhs, rhs) -> $VectorN<S> { $VectorN::new($(lhs.$field * rhs.$field),+) }
-        });
-
         impl_assignment_operator!(<S: BaseNum> MulAssign<S> for $VectorN<S> {
             fn mul_assign(&mut self, scalar) { $(self.$field *= scalar);+ }
         });
-        impl_assignment_operator!(<S: BaseNum> MulAssign<$VectorN<S> > for $VectorN<S> {
-            fn mul_assign(&mut self, other) { $(self.$field *= other.$field);+ }
-        });
 
         impl_operator!(<S: BaseNum> Div<S> for $VectorN<S> {
             fn div(vector, scalar) -> $VectorN<S> { $VectorN::new($(vector.$field / scalar),+) }
         });
-        impl_operator!(<S: BaseNum> Div<$VectorN<S> > for $VectorN<S> {
-            fn div(lhs, rhs) -> $VectorN<S> { $VectorN::new($(lhs.$field / rhs.$field),+) }
-        });
         impl_assignment_operator!(<S: BaseNum> DivAssign<S> for $VectorN<S> {
             fn div_assign(&mut self, scalar) { $(self.$field /= scalar);+ }
         });
-        impl_assignment_operator!(<S: BaseNum> DivAssign<$VectorN<S> > for $VectorN<S> {
-            fn div_assign(&mut self, other) { $(self.$field /= other.$field);+ }
-        });
 
         impl_operator!(<S: BaseNum> Rem<S> for $VectorN<S> {
             fn rem(vector, scalar) -> $VectorN<S> { $VectorN::new($(vector.$field % scalar),+) }
         });
-        impl_operator!(<S: BaseNum> Rem<$VectorN<S> > for $VectorN<S> {
-            fn rem(lhs, rhs) -> $VectorN<S> { $VectorN::new($(lhs.$field % rhs.$field),+) }
-        });
         impl_assignment_operator!(<S: BaseNum> RemAssign<S> for $VectorN<S> {
             fn rem_assign(&mut self, scalar) { $(self.$field %= scalar);+ }
         });
-        impl_assignment_operator!(<S: BaseNum> RemAssign<$VectorN<S> > for $VectorN<S> {
-            fn rem_assign(&mut self, other) { $(self.$field %= other.$field);+ }
-        });
+
+        impl<S: BaseNum> ElementWise for $VectorN<S> {
+            #[inline] fn add_element_wise(self, rhs: $VectorN<S>) -> $VectorN<S> { $VectorN::new($(self.$field + rhs.$field),+) }
+            #[inline] fn sub_element_wise(self, rhs: $VectorN<S>) -> $VectorN<S> { $VectorN::new($(self.$field - rhs.$field),+) }
+            #[inline] fn mul_element_wise(self, rhs: $VectorN<S>) -> $VectorN<S> { $VectorN::new($(self.$field * rhs.$field),+) }
+            #[inline] fn div_element_wise(self, rhs: $VectorN<S>) -> $VectorN<S> { $VectorN::new($(self.$field / rhs.$field),+) }
+            #[inline] fn rem_element_wise(self, rhs: $VectorN<S>) -> $VectorN<S> { $VectorN::new($(self.$field % rhs.$field),+) }
+
+            #[cfg(feature = "unstable")] #[inline] fn add_assign_element_wise(&mut self, rhs: $VectorN<S>) { $(self.$field += rhs.$field);+ }
+            #[cfg(feature = "unstable")] #[inline] fn sub_assign_element_wise(&mut self, rhs: $VectorN<S>) { $(self.$field -= rhs.$field);+ }
+            #[cfg(feature = "unstable")] #[inline] fn mul_assign_element_wise(&mut self, rhs: $VectorN<S>) { $(self.$field *= rhs.$field);+ }
+            #[cfg(feature = "unstable")] #[inline] fn div_assign_element_wise(&mut self, rhs: $VectorN<S>) { $(self.$field /= rhs.$field);+ }
+            #[cfg(feature = "unstable")] #[inline] fn rem_assign_element_wise(&mut self, rhs: $VectorN<S>) { $(self.$field %= rhs.$field);+ }
+        }
+
+        impl<S: BaseNum> ElementWise<S> for $VectorN<S> {
+            #[inline] fn add_element_wise(self, rhs: S) -> $VectorN<S> { $VectorN::new($(self.$field + rhs),+) }
+            #[inline] fn sub_element_wise(self, rhs: S) -> $VectorN<S> { $VectorN::new($(self.$field - rhs),+) }
+            #[inline] fn mul_element_wise(self, rhs: S) -> $VectorN<S> { $VectorN::new($(self.$field * rhs),+) }
+            #[inline] fn div_element_wise(self, rhs: S) -> $VectorN<S> { $VectorN::new($(self.$field / rhs),+) }
+            #[inline] fn rem_element_wise(self, rhs: S) -> $VectorN<S> { $VectorN::new($(self.$field % rhs),+) }
+
+            #[cfg(feature = "unstable")] #[inline] fn add_assign_element_wise(&mut self, rhs: S) { $(self.$field += rhs);+ }
+            #[cfg(feature = "unstable")] #[inline] fn sub_assign_element_wise(&mut self, rhs: S) { $(self.$field -= rhs);+ }
+            #[cfg(feature = "unstable")] #[inline] fn mul_assign_element_wise(&mut self, rhs: S) { $(self.$field *= rhs);+ }
+            #[cfg(feature = "unstable")] #[inline] fn div_assign_element_wise(&mut self, rhs: S) { $(self.$field /= rhs);+ }
+            #[cfg(feature = "unstable")] #[inline] fn rem_assign_element_wise(&mut self, rhs: S) { $(self.$field %= rhs);+ }
+        }
 
         impl_scalar_ops!($VectorN<usize> { $($field),+ });
         impl_scalar_ops!($VectorN<u8> { $($field),+ });
@@ -331,12 +321,6 @@ macro_rules! impl_vector {
 
 macro_rules! impl_scalar_ops {
     ($VectorN:ident<$S:ident> { $($field:ident),+ }) => {
-        impl_operator!(Add<$VectorN<$S>> for $S {
-            fn add(scalar, vector) -> $VectorN<$S> { $VectorN::new($(scalar + vector.$field),+) }
-        });
-        impl_operator!(Sub<$VectorN<$S>> for $S {
-            fn sub(scalar, vector) -> $VectorN<$S> { $VectorN::new($(scalar - vector.$field),+) }
-        });
         impl_operator!(Mul<$VectorN<$S>> for $S {
             fn mul(scalar, vector) -> $VectorN<$S> { $VectorN::new($(scalar * vector.$field),+) }
         });
diff --git a/tests/vector.rs b/tests/vector.rs
index b076f8b..7a41889 100644
--- a/tests/vector.rs
+++ b/tests/vector.rs
@@ -40,13 +40,6 @@ macro_rules! impl_test_add {
         assert_eq!(&$v + &$v, $v + $v);
         assert_eq!(&$v + $v, $v + $v);
         assert_eq!($v + &$v, $v + $v);
-        // vector + scalar ops
-        assert_eq!($v + $s, $VectorN::new($($v.$field + $s),+));
-        assert_eq!($s + $v, $VectorN::new($($s + $v.$field),+));
-        assert_eq!(&$v + $s, $v + $s);
-        assert_eq!($s + &$v, $s + $v);
-        // commutativity
-        assert_eq!($v + $s, $s + $v);
     )
 }
 
@@ -57,23 +50,11 @@ macro_rules! impl_test_sub {
         assert_eq!(&$v - &$v, $v - $v);
         assert_eq!(&$v - $v, $v - $v);
         assert_eq!($v - &$v, $v - $v);
-        // vector - scalar ops
-        assert_eq!($v - $s, $VectorN::new($($v.$field - $s),+));
-        assert_eq!($s - $v, $VectorN::new($($s - $v.$field),+));
-        assert_eq!(&$v - $s, $v - $s);
-        assert_eq!($s - &$v, $s - $v);
-        // commutativity
-        assert_eq!($v - $s, -($s - $v));
     )
 }
 
 macro_rules! impl_test_mul {
     ($VectorN:ident { $($field:ident),+ }, $s:expr, $v:expr) => (
-        // vector * vector ops
-        assert_eq!($v * $v, $VectorN::new($($v.$field * $v.$field),+));
-        assert_eq!(&$v * &$v, $v * $v);
-        assert_eq!(&$v * $v, $v * $v);
-        assert_eq!($v * &$v, $v * $v);
         // vector * scalar ops
         assert_eq!($v * $s, $VectorN::new($($v.$field * $s),+));
         assert_eq!($s * $v, $VectorN::new($($s * $v.$field),+));
@@ -86,11 +67,6 @@ macro_rules! impl_test_mul {
 
 macro_rules! impl_test_div {
     ($VectorN:ident { $($field:ident),+ }, $s:expr, $v:expr) => (
-        // vector / vector ops
-        assert_eq!($v / $v, $VectorN::new($($v.$field / $v.$field),+));
-        assert_eq!(&$v / &$v, $v / $v);
-        assert_eq!(&$v / $v, $v / $v);
-        assert_eq!($v / &$v, $v / $v);
         // vector / scalar ops
         assert_eq!($v / $s, $VectorN::new($($v.$field / $s),+));
         assert_eq!($s / $v, $VectorN::new($($s / $v.$field),+));
@@ -101,11 +77,6 @@ macro_rules! impl_test_div {
 
 macro_rules! impl_test_rem {
     ($VectorN:ident { $($field:ident),+ }, $s:expr, $v:expr) => (
-        // vector % vector ops
-        assert_eq!($v % $v, $VectorN::new($($v.$field % $v.$field),+));
-        assert_eq!(&$v % &$v, $v % $v);
-        assert_eq!(&$v % $v, $v % $v);
-        assert_eq!($v % &$v, $v % $v);
         // vector % scalar ops
         assert_eq!($v % $s, $VectorN::new($($v.$field % $s),+));
         assert_eq!($s % $v, $VectorN::new($($s % $v.$field),+));